Highest temperature in Tokyo on August 7?

Platform comparison

Market context

Polymarket is pricing this Tokyo Haneda Airport temperature contract at **0% YES**, which implies the market is treating a qualifying top-end reading on 7 August 2026 as effectively absent despite summer heat being normal for the date. The contract settles against the **highest temperature in Weather Underground’s Daily Observations table**, not the Day High & Low summary, so traders on USDC-linked conditional tokens on Polygon need to follow the station-level observation feed rather than a generic daily headline.

That zero price sits against a climatological backdrop where Tokyo in August usually sees daytime highs around **31°C** and frequently pushes into the low-to-mid 30s. AccuWeather’s August outlook for Tokyo shows forecast highs in the **82°F to 90°F** range, while JMA’s August daily data for Tokyo and Haneda already shows early-month maxima well above 33°C, with Haneda at **35.6°C** on 1 August and **33.0°C** on 2 August[1][2]. In other words, the market is not asking whether Tokyo is warm; it is asking whether Haneda’s official observation table prints into the relevant temperature band on this specific day.

The main catalysts are the live weather path through the day, especially any late-morning or afternoon spike before the settlement window closes, plus how Weather Underground renders the station’s observation history after the fact. Traders should watch the short-range Tokyo forecast, any heat-advisory reporting from Japanese forecasters, and whether cloud, rain, or sea-breeze effects cap the airport reading below the market’s bucket thresholds[1][12][19]. With settlement tied to the recorded maximum rather than the forecast, the key dependency is the actual Haneda station trace, not broader Tokyo averages.

Sources: 1 · 2 · 3 · 4 · 5

Methodology

This page is a comparison snapshot: one live quote, four reference venues with their key attributes, and a single execution path — every trade button routes to PolyGram, which mirrors the Polymarket order book directly.

Resolution & payout

Settlement runs on-chain. Polymarket's contract logic separates YES and NO shares as conditional tokens; at resolution the winning share lifts to $1.00 and the losing one to $0. The outcome input comes from the UMA Optimistic Oracle, which secures against bad resolution with a bond + dispute window.

Once finalised, the smart contract pays USDC to the holders' wallets within minutes — no withdrawal fees beyond Polygon network gas. Kalshi settles in USD via CFTC clearance, Betfair in account currency net of commission, Manifold in play-money mana with no cash-out.

UK Frequently Asked Questions

How does resolution work?

Through the UMA Optimistic Oracle on Polygon: a proposer submits the outcome, a two-hour challenge window opens, and USDC payouts settle automatically once the result is final.

What's the difference between YES and NO shares?

A YES share pays $1.00 if the event happens, $0 otherwise. A NO share pays $1.00 if the event doesn't happen. The market price between 0¢ and 100¢ is the implied probability.

Is Polymarket legal in the UK?

Polymarket is accessible to UK traders but is not UKGC-licensed. It operates under US CFTC jurisdiction. UK residents face no domestic legal prohibition on using it, but UKGC consumer protections do not apply. For UKGC-regulated alternatives, Betfair Exchange and Smarkets offer similar prediction-style markets.

Do I pay tax on prediction market profits in the UK?

UKGC-licensed platform profits (Betfair, Smarkets) are typically tax-free gambling winnings for UK individuals. Polymarket profits involve USDC crypto transactions, which HMRC treats as Capital Gains Tax events. Keep full transaction records and report via Self Assessment if gains exceed £3,000 per tax year.

How do I deposit on Polymarket from the UK?

UK traders typically fund Polymarket via Coinbase UK, Kraken or Revolut — buying USDC with GBP and transferring to a Polygon-compatible wallet (MetaMask, Coinbase Wallet). Polymarket's onboarding walks you through the bridging process. Typical GBP-to-USDC conversion costs 0.5–1%.